We are pleased to announce WikiXMLDB which allows querying Wikipedia in XQuery.
We have parsed English Wikipedia into a well-structured XML document (21 Gb in size) and loaded it into Sedna XML database (http://modis.ispras.ru/sedna). With WikiXMLDB demo you can run predefined or your own XQuery queries via Web interface.
Querying Wikipedia in XQuery allows you to implement many interesting applications. Read "Use case" section (http://wikixmldb.dyndns.org/help/use-cases) for more details.
Enjoy it!
Maria Grineva Sedna team